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Message-ID: <cf420c0c0e64d9ee9681bf81d3dd84a2a048e2db.camel@gmx.de>
Subject: Re: [RFC v2 12/34] mm, slub: move disabling/enabling irqs to
 ___slab_alloc()
From:   Mike Galbraith <efault@gmx.de>
To:     Vlastimil Babka <vbabka@suse.cz>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, Christoph Lameter <cl@linux.com>,
        David Rientjes <rientjes@google.com>,
        Pekka Enberg <penberg@kernel.org>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc:     Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        Thomas Gleixner <tglx@linutronix.de>,
        Mel Gorman <mgorman@techsingularity.net>,
        Jesper Dangaard Brouer <brouer@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Jann Horn <jannh@google.com>
Date:   Tue, 06 Jul 2021 06:38:33 +0200
In-Reply-To: <20210609113903.1421-13-vbabka@suse.cz>
References: <20210609113903.1421-1-vbabka@suse.cz>
         <20210609113903.1421-13-vbabka@suse.cz>
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Greetings,

On Wed, 2021-06-09 at 13:38 +0200, Vlastimil Babka wrote:
> @@ -3313,6 +3320,8 @@ int kmem_cache_alloc_bulk(struct kmem_cache *s,
> gfp_t flags, size_t size,
>  			 */
>  			c->tid =3D next_tid(c->tid);
>
> +			local_irq_enable();
> +
>  			/*
>  			 * Invoking slow path likely have side-effect
>  			 * of re-populating per CPU c->freelist

This addition should have been followed by removal of the one in the
error path.  At the end of the series, RT ends up doing a double
local_unlock_irq() instead of post ___slab_alloc() slub_put_cpu_ptr().

	-Mike